$10,000 is invested at two different rates. $2,500 is invested at 4%, and the rest is invested at 5%. how much interest is earned at the end of one year? show all work for full credit.

answer: 1 + 1 = 11

step-by-step explanation:

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.